Air pressure operated dispenser

ABSTRACT

A dispensing device in which the product to be dispensed is aspirated and sprayed by the discharged pressurized air. A valve assembly has a product flow path therethrough and a compressed air flow path therethrough. The valve stem of the assembly is actuated to open the flow paths, and aspirating means is provided at the upper end of said stem for bringing one end of each of said flow paths together. A piston-cylinder assembly is provided on the device having a cylinder with one end around the end of the compressed air flow path, a piston slidable in the cylinder, and a piston rod on said piston and extending out of the other end of said cylinder. A product containing sac has a neck thereon sealed around the end of the product flow path. An actuator means is connected between the piston rod and the valve assembly for moving the valve stem relative to the valve body for opening the flow paths when the piston is moved to the inner end of the cylinder adjacent the valve assembly to provide a predetermined amount of compressed air.

United States Patent Marand 51 June 27, 1972 54 AIR PRESSURE OPERATEDDISPENSER $7 Ansnucr [72] Inventor: Jean Marand, Norwalk, Conn. Adispensing device in which the product to be dispensed is i aspiratedand sprayed by the discharged pressurized air. A [73] Ass'gnee' Comer-onvalve assembly has a product flow path therelhrough and a [22] Filed:June 9, I970 compressed air flow path therethrough. The valve stem ofthe assembly is actuated to open the flow paths, and aspirating Appl'means is provided at the upper end of said stem for bringing one end ofeach of said flow paths together. A piston-cylinder Cl "2 222/4005, 22/0 assembly is provided on the device having a cylinder with one l endaround the end of the compressed air flow path, a piston [51 Int. Cl.867d 5/54 lidable in the cylinder, and a piston rod on said piston andexsell'dlm 4005. tending out of the other end of said cylinder. Aproduct con- 222/503; 125/276- 278 taining sac has a neck thereon sealedaround the end of the product flow path. An actuator means is connectedbetween [56] Reimnm the piston rod and the valve assembly for moving thevalve UNITED STATES PATENTS stem relative to the valve body for openingthe flow paths when the piston is moved to the inner end of the cylinderad- 2.3$3,343 9/1958 Bam g r 2 x jacent the valve assembly to provide apredetermined amount 3,265,3l2 8/1966 Curti .222/402 X f mpressed air3,389,837 6/1968 Marand ..222/l93 8 Claims, 3 Drawing Figures PrimaryExaminer- Robert B. Reeves Assistant Examiner--Thomas E. KocovskyAnorneywenderoth, Lind & Ponack s9 42 40a M .41

l 2| w 23 o q a j 4-45 w-u F- s -|0 3 s4 6 q c I l6 i so x 9 32 j S a ae l a 45 //1 Mil 49 47 AIR PRESSURE OPERATED DISPENSER BACKGROUND OF THEINVENTION This invention relates to a dispenser for fluids, and moreparticularly to a device for aspirating a fluid and dispensing it as aspray by means of compressed air.

PRIOR ART The art of dispensing fluid materials is very highlydeveloped. More recently there have been great advances in the art ofdispensing fluid materials by means of a compressed propellant whilekeeping the fluid and propellant separate prior to dispensing. Theserecently developed so-called double aerosol type dispensers are quitesatisfactory, but nevertheless have some disadvantages, particularlywhere they must be made in small sizes. Many of these disadvantages arealso common to the single phase dispensers, where the propellant and thematerial to be dispensed are stored in the mixed condition in thedispenser prior to dispensing.

Among these disadvantages is leakage of propellant from the propellantcartridge during storage, which reduces the shelf life of the dispenser.Additionally, the problem of exactly matching the amount of propellantwith the amount of material to be dispensed is often difficult becauseof this leakage problem. Also because of differences between the variousmaterials being dispensed, a proper amount of propellant for onematerial will not suffice or will be in excess of that necessary fordispensing all of another material. In the first instance, part of theproduct is wasted, and in the second instance, part of the propellant iswasted.

In addition, if it is desired to dispense only a measured quantity ofmaterial, special valving means must be developed. Otherwise, the amountof material dispensed is proportional to the time of actuation of thedevice, and there is no way to accurately insure that the user willproperly time the actuation to dispense the desired measured quantity.

A further disadvantage is that with compressed gas type propellants,when the propellant is running low, the dispensing of the last of thematerial to be dispensed can be carried out only at a very slow rate, ascompared to when the dispenser is initially filled with propellant, whendispensing takes place rapidly.

Moreover, when conventional aerosol propellants are used to dispensemedicaments in inhaler type devices, potentially toxic propellants areinhaled by the user along with the medicament. In many cases, this isundesirable and pharmaceutical marketers would prefer to have theproduct dispensed by air instead of a chemical vapor conventionally usedas propellants.

Many of these disadvantages could be overcome if, instead of usingcompressed conventional propellant gases, air was used as a propellantand was compressed each time the dispensing operation was to be carriedout. Conventional squeeze bulb and poston-cylinder atomizers operatesomewhat in this fashion, but have the serious drawback that thecompression is carried out gradually, and the aspiration is thusgradual, the amount of material being dispensed being dependant on howfast and with what force the squeeze bulb or the piston-cylinder meansis operated.

OBJECTS AND SUMMARY OF THE INVENTION It is an object of the presentinvention to provide a dispensing device which utilizes compressed airfor aspiration in a manner so as to overcome all of the reciteddisadvantages of the aerosol type dispensers.

It is a further object of the present invention to provide a dispensingdevice which utilizes compressed air that is compressed each timedispensing takes place, but which releases the compressed air suddenlyonly after the pressure has been built to the maximum.

It is a still further object of the present invention to provide adispensing device which utilizes compressed air for dispensing, whichdispenses a measured amount of material at each actuation of the device,which is extremely safe to use, and which cannot dispense more than themeasured amount of material.

It is a still further object of the present invention to provide adispensing device which can be stored without loss of a propellant andwhich therefore has a shelf life limited only by the life of thematerial to be dispensed, and which can also be stored without fear ofan explosion of a compressed propellant.

These objects are achieved by providing a dispensing device which has avalve assembly with a valve body and a hollow valve stem movable throughsaid valve body. The valve assembly has a product flow path therethroughand a compressed air flow path therethrough, part of one of these flowpaths being through the stern. Aspirating means are provided at theupper end of the stem to bring the flow paths together. Obturating meansare operatively associated with the stem for obturating the flow paths.The flow paths open out of the bottom of the valve body. A pistoncylinder assembly has a cylinder around the end of the compressed airflow path having a piston slidable therein, and sealed around the end ofthe product flow path is the neck of a product containing sac. A pistonrod is connected to the piston for moving the piston into the cylinder,and actuator means is connected between the piston rod and the stern formoving the stem and the valve body together to open the flow paths whenthe piston reaches the inner end of the cylinder, thus releasing thecompressed air from the cylinder and opening the flow path for theproduct for aspirating the product and dispensing it in a spray.

BRIEF DESCRIPTION OF THE DRAWINGS Other and further features of theinvention will be described in the following specification and claims,taken with the accompanying drawings, in which:

FIG. I is a sectional elevation view of the dispensing device accordingto the present invention, with the parts in positions for the start of adispensing operation;

FIG. 2 is a sectional elevation view of the upper part of the deviceshown in FIG. 1; and

FIG. 3 is a view similar to FIG. 2 in which the parts are shown in theirpositions at the end of a dispensing operation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first toFIGS. 1 and 2, there is shown a dispensing device according to theinvention. The dispensing device is constituted by a valve assembly, apiston-cylinder assembly, a product containing sac, a housing enclosingthese elements, and an actuating linkage.

The valve assembly is similar to that disclosed in U.S. Pat. applicationSer. No. 778,905 in the name of Marand. It has a valve body 10 having ahollow interior ll, which opens out of the top of the valve body 10. Abore 12 extends downward from the hollow interior I1 and opens into adownward open recess 13 in the bottom of the valve body 10. Positionedin the downward open recess 13 is an annular obturating gasket 14.

A hollow valve stem 15 extends through the hollow interior 11, and has acylindrical portion 18 extending through the bore 12 and spaced onlyslightly therefrom, so that the surface defining the bore 12 forms aloose bearing for the valve stem 15. A conical head 16 is provided onthe bottom end of the stem 15, and between the cylindrical portion 18and the conical head 16 is a reduced diameter portion l9 in which theinner edge of the annular gasket M is tightly engaged.

The stem has a hollow bore 17 therein, and from the lower end of thebore 17 extend vertical passages 20, which open out of the stem in thereduced diameter portion 19. In the rest position of the stern, as shownin FIG. 1, in which the stem is in the raised postion relative to thevalve body 10, the inner edge of the annular gasket 14 closes off orobturates the openings at the lower ends of the vertical passages 20.

The valve stem has a flange 21 thereon. A return spring 23 is positionedbetween the flange and the bottom of the hollow interior 1!, and tendsto urge the stem 15 in the upward direction. Fin-like projections 24 areprovided of the inner surface of the valve body and project into thehollow interior 11. The upper ends of the projections 24 are at a levelsuch that they are abutted by the flange 21 and act as stops for thedownward movement of the stem 15.

On the exterior peripheral surface of the upper part of the stem abovethe flange 21 are a plurality of radially projecting ribs 25 extendingparallel to the axis of the stem, and defin ing between them passages26. At the lower ends of the ribs 25 and outwardly thereof on the upperpart of the flange 2! is a downward and outward tapered surface 28.Engaged with this surface 28 is the inner portion of the downward facingsurface of a further annular obturating gasket 29 for obturating flow ofthe product. This gasket has the outer portion of the downward facingsurface engaged with the upper end of the valve body 10, so that in thenormal or rest position, as shown in H6. 1, the annular gasket 29 closesoff the top of the hollow interior 11 between the stem and the valvebody.

Extending downward from the hollow interior 11 on one side of the valvebody [0 is a product passage 33 which opens into a further downward openrecess 34 in the bottom of the valve body.

The valve stem 15 has an upper cylindrical portion 37, which is integralwith the outer edges of the ribs 25, and which extends upward beyond theend of the portion of the valve stem 15 having the hollow bore 17therein. The interior of the upper cylindrical portion 37 defines alarger upward opening recess 38 at the upper end of the valve stem 15.in the upper portion of the valve stem within the upper cylindricalportion 37 is a smaller upward opening recess 38a into which is fittedaspirating means in the form of a nozzle insert generally indicated at39. The nozzle insert has a Venturi portion 40, which has the lowerportion fitted into the recess 38a. The Venturi portion 40 is longerthan the recess 38a is deep, so that the Venturi portion extends beyondthe outer end of the recess 38a. The nozzle insert has a larger diameterportion 41 on the upper end thereof, the outer diameter of which fitstightly within the upward opening recess 38. This portion 41, togetherwith the upper ends of the ribs 25, defines a product supply chamber 44.The Venturi nozzle insert 39 has a Venturi nozzle 40a therein, withradial product passages 42 opening into it through the Venturi portion40 from the product supply chamber 44.

The piston-cylinder assembly has a cylinder 32, the upper end of whichis in sealing engagement with said valve assembly around bore 12. Inthis embodiment it is engaged with the lower surface of the annularobturating gasket 14. The upper end of the cylinder 32 is thus closed bythe gasket l4 and the conical head 16 extending through the gasket. Thecylinder 32 has a flange 32a at the end thereof remote from the valveassembly. The outside diameter of the flange 32a is preferably about thesame as the outside diameter of the valve body 10.

A piston 45 is slidable in the cylinder 32 and a piston ring 46 ispositioned in a groove around the piston. A piston rod 47 extends fromthe piston 45 out through the open end of the cylinder 32 and a pressuremember 48 is mounted on the end of the rod. A vent bore 49 extendsthrough the rod and the piston.

There is defined between the flange 32a and the lower end of the valvebody 10 an annular recess in which is positioned an annular flexiblecollapsible prouuct containing sac 35. The product containg sac 35 has adischarge outlet 36 on the upper end thereof which extends upward andinto sealing engagement with the valve body in the recess 34 into whichthe product passage 33 opens.

Surrounding the above described parts and holding them in the describedrelationship is a housing, which, in this embodiment, is a two parthousing. The upper part 31 has atop flange 31a flanged over the uppersurface of the further annular gasket 29 and a bottom flange 31b turnedinto groove 10a provided in the outer peripheral wall of the valve body10. The upper housing part 31 thus tightly clamps the valve body 10 andthe annular gasket 29 together. A lower housing part 30 has the upperend threaded to the valve body 10 and extends downward so as to definethe outer periphery of the annular recess for the sac 35. The bottom 30aof the lower housing part extends inwardly and supports the flange 320on the end of cylinder 32. The bottom has an opening therein for pistonrod 47. The lower housing part 30 also has openings 30a in the outerperipheral wall thereof to admit air to the annular recess in which ispositioned the product containing sac 35.

Extending outwardly from the bottom of the lower housing part 30 arediametrally opposite finger grips 50, which, in this embodiment, areintegrally formed with the housing pan 30.

Actuator means are provided, which, in this embodiment, comprise anactuator sleeve 52 on the upper cylindrical portion 37 of the valve stem15. The actuator sleeve 52 has the upper end flanged over the end of theupper cylindrical por tion 37, and has a laterally projecting flange 520on the lower end thereof. Engaged with the flange 520 are twodiametrally opposed levers 53 which are pivotally mounted on projections51 mounted on the top flange 31a of the upper body portion 31. Pivotallyconnected to the free ends of the levers 53 is an actuator 54 which is agenerally U-shaped frame which extends along the sides of the device andbeneath the end of the lower housing portion 30, extending throughapertures 50a in the finger grips 50. The closed end of the actuator 54has an aperture therein through which the piston rod 47 extends.

In operation, starting with the parts in the positions shown in FIGS. 1and 2, the device is gripped by the finger grips 50, and a finger isplaced over the end of the bore 49 opening out of the pressure member48. A force is then exerted to force the piston 45 into the cylinder 32.This causes the air pressure in the cylinder to build up, the cylinderbeing closed at one end by the valve assembly and at the other end bythe finger over the vent bore 49. This movement is continued until thepiston nears the bottom of the cylinder, at which time the pressuremember 48 abuts the actuator 54. At this point, the pressure within thecylinder has been built up to a maximum. Further movement of thepressure member 48, in addition to moving the piston, also moves theactuator in the same direction the piston is moving. This causespivoting of the levers 53 so as to move the actuator sleeve 52 towardthe valve assembly, thus moving the valve stem 15 into the valveassembly.

Up to this point, the bore 17 in the stem has been sealed off from theinterior of the cylinder 32 by the obturating gasket 14, whichcompletely seals off the vertical passages 20. In addition, the hollowinterior 11 is sealed off from the passages 26 between the ribs 25 alongthe outside of the upper portion of the stem 15 by the gasket 29 and itssealing engagement with the tapered surface 28 on the upper part offlange 21 and with the upper end of the valve body 10 around the hollowinterior It.

As shown in FIG. 3, upon movement of the valve stem 15 into the valvebody 10 by movement of the actuator sleeve 52, the hollow stem 15 movesdownward through the hollow interior 11, two actions take place. One ofthese is the flexing downward of the obturating gasket 14, so that theupper surface around the hole therethrough is engaged by the downwardlyand inwardly tapered surface leading to the reduced diameter portion 19.The inner periphery of the obturating gasket 14 is moved away from thelower ends of vertical passages 20, thus opening a compressed air flowpath from the interior of cylinder 32 through the bore 17 to the Venturiportion 40 of nozzle insert 39.

Depending on the exact construction, slightly before or slightly afterthe opening of the passages 20, the downward flexing of the annulargasket 29 proceeds to a point where the downwardly and inwardly taperedportion of the lower end of the upper cylindrical portion 37 engages theupper surface of annular gasket 29, and the inner periphery of thegasket 29 moves away from the tapered surface 28 on the upper part offlange 21. This establishes an opening between the hollow interior 11and the passages 26, and a product flow path from the interior of thehollow interior 11 and the passages 26. A product supply chamber 44 issealed off from the atmosphere. The reduced pressure in the Ventruinozzle 40a is thus communicated to this flow path through the radialproduct passages 42, and the product to be dispensed is aspirated fromthe product containing sac 35. Aspiration will continue until thecompressed air in the cylinder 32 is exhausted.

As the product is aspirated from the product containing sac, the sacwill collapse under the efi'ect of the pressure of the atmosphere aroundthe dispensing device, which acts on the sac 35 through the openings 30bin the lower housing part 30.

After completion of aspiration, release of the force on the actuator 54for moving the hollow stem 15 inwardly of the valve assembly enables thereturn spring 23 to urge the hollow stem 15 to the rest position of FIG,2, thereby returning the parts of the valve assembly to the positionshown in FIG. 1. The finger is then removed from the end of vent bore 49and the rod 47 and piston 45 are drawn out of the cylinder to the FIG. 1position.

It will be understood that the inward movement of the stem 15 is limitedby the engagement of flange 21 with the projections 24 in the hollowinterior of valve body 10, and that movement of the stem 15 in theoutward direction is limited by the engagement of the flange 21 with thegasket 29, which in turn is restrained by the top flange 31a on theupper housing part 3 l The device has many advantages. While thecompression of the air is carried out gradually, the release of thecompressed air occurs suddenly and only after compression has reached amaximum. Thus, the maximum aspiration effect is produced rather than agradual aspiration, such as is produced with conventional squeeze bulbor piston-cylinder type atomizers. Moreover, the device is extremelycompact, the housing parts 30 and 31 serving to hold most of the variousparts together, and the use of the cylinder and piston enabling theprovision of the product containing sac in the recess defined thereby.The provision of the nozzle insert 39 within the upper end of the hollowstem makes this part compact and especially useful for dispensing aproduct in a direction substantially axially of the device. The use ofthe piston-cylinder arrangement eliminates the need for a compressed orliquefied propellant and a separate container therefor, which in turneliminates any problems of compatability of the propellant with theproduct being dispensed from the sac. In addition, it eliminatesproblems of shelf life of the device due to leakage of any suchpropellant container, and always assures that there will be a supply ofair under pressure to aspirate the product.

Because the amount of compressed air available for aspiration isinherently limited by the size of the device, it inherently dispenses ameasured dose. By properly designing the pistoncylinder assembly andproperly dimensioning the various orifices and flow paths within thevalve assembly, it is possible to control the amount of the productdispensed. The amount of product dispensed depends mainly on the size ofthe piston chamber. This results in the delivery of a specific amount ofair, which in turn aspirates a specific quantity of product. Thepressure created in the chamber depends mainly on the length of thepiston stroke, and this pressure will effect the characteristics of thespray pattern of product delivered. If the structure is changed so thatthe size of the pressure chamber, i.e. the cylinder 32, remainsconstant, but the stroke of piston 45 is longer or shorter, the pressurecreated will be different, but the quantity of air delivered will remainabout the same. Thus, the spray characteristics will change, but thequantity of product delivered will remain basically the same.Conversely, if the size of the pressure chamber is changed (increased ordecreased in size) and the length of the piston stroke is kept the samethe characteristic of the spray pattern will remain generally the same,but the quantity of product delivered will either increase or decrease.Varying the size of the various orifices will also effect the spraypattern and delivery rates, and

any desired spray pattern and amount of dispensed material can beobtained by proper design of the device.

Because of the fact that the device provides only a predetermined, i.e.by the design of the device, amount of compressed air for aspirating,the device can never dispense more than a given amount during any oneactuation cycle. The device is therefore inherently extremely safe foruse in dispensing medicaments, for example. Oral inhalation ofmedicaments is made safer since only air and medicament, rather thanpotentially toxic propellents and medicament, are taken into the lungs.

Many variations in the construction of the device will be apparent. Thehousing for the valve assembly has been described as having two parts,an upper part 31 and a lower part 30. This is for convenience inassembly, it being easier to simply flange under the flange 31b with theprojections 51 in the desired position, and then thread the lowerhousing part 30 onto the valve body 10. However, these two parts couldbe integral, and the cylindrical wall thereof simply indented into thegroove 100, or beneath the bottom of the valve body 10. The cylinder 32has been shown as separate from the lower housing part 30. This makes itpossible to simply position the cylinder against the gasket 14 and thenthread the lower housing part onto the valve body without it beingnecessary to turn the cylinder. This prevents the upper end of thecylinder 32 from cutting or scoring the gasket 14. However, these twoparts could be made integral, and the housing 30 could be crimped intoplace. The actuator means could be difl'erent. For example, the valveassembly and housing could be placed in a holder having finger gripsthereon with the end of the valve stem abutted against the holder, andthe inner end of the cylinder shaped to block movement of the pistonwhen it reaches the inner end. Engagement of the piston with theblockage would force the valve assembly toward the valve stem, with thesame results as the movement of the valve stem into the valve assembly.Instead of having a simple vent bore blocked by the finger of the user,the piston could be provided with a one way valve permitting flow of aironly into the cylinder when the piston is being drawn out of thecylinder,

The dispenser device described above is self contained and can be usedto dispense a material, such as a medicament or a deodorant, directly tothe location at which it is to be used.

It will be appreciated that although the terms upper, lower, top andbottom have been used in describing the device according to theinvention, these terms have been used for convenience in referring tothe device in the position in which it is shown in the drawings, and arenot intended to be any limitation on the position in which the devicecan be used.

The terms "cylinder" and cylindricaP as used throughout thespecification are not intended to be limited to right circu larcylinders, but are intended to include any desired shape generated by astraight line moving parallel to an axis, so that the cross-section ofthe cylinder can be circular, square, triangular, or any other suchgeometrical shape. Likewise, the term annular is intended to include anyshape which can fit around any such cylinder,

It will also be appreciated that while the seals between the variouspistons and cylinders have been shown as gaskets sliding along the wallsthereof, these gaskets can be omitted in many instances and replaced byfriction fits between the parts.

What is claimed is:

l. A dispensing device comprising: a valve assembly having a valve body,a valve stem movable through said valve body, said valve assembly havinga product flow path therethrough and a compressed air flow paththerethrough, part of one of said flow paths being through said stem,obturating means associated with said stem for obturating said flowpaths and actuated by said stem on movement of said stem to open theflow paths, and aspirating means at the upper end of said stem forbringing one end of each of said flow paths together, the other ends ofthe flow paths opening out of the valve body remote from said aspiratingmeans, a piston-cylinder assembly having a cylinder with one end aroundthe end of the compressed air flow path, a piston slidable in saidcylinder, a piston rod on said piston and extending out of the other endof said cylinder; product containing means coupled to the end of theproduct flow path remote from the aspirating means; and said piston andpiston rod and said valve assembly being operatively associated formoving said valve stem relative to said valve body for causing saidobturating means to open said flow paths when said piston is moved tothe inner end of said cylinder adjacent said valve assembly.

2. A dispensing device comprising: a valve assembly having a valve body,a hollow valve stem movable through said valve body, said valve assemblyhaving a product flow path therethrough and a compressed air flow paththerethrough, part of one of said flow paths being through said stem,obturating means associated with said stem for obturating said flowpaths and actuated by said stern on movement of said stem to open theflow paths, and aspirating means at the upper end of said stern forbringing one end of each of said flow paths together, the other ends ofthe flow paths opening out of the bottom of the valve body; apiston-cylinder assembly having a cylinder with one end around the endof the compressed air flow path, a piston slidable in said cylinder, apiston rod on said piston and extending out of the other end of saidcylinder; a product containing sac having a neck thereon sealed aroundthe end of the product flow path; and an actuator means connectedbetween said piston rod and said valve assembly for moving said valvestem relative to said valve body for causing said obturating means toopen said flow paths when said piston is moved to the inner end of saidcylinder adjacent said valve assembly.

3. A dispensing device as claimed in claim 2 in which said piston rodand said piston have a bore therethrough.

4. A dispensing device as claimed in claim 2 in which said cylinder isengaged with the axial portion of said valve assembly, a housing aroundsaid valve assembly and said cylinder and defining an annular spacearound said cylinder, said product sac being an annular sac and beingpositioned in said space, said housing having at least one aperturetherein for admitting air to said space.

5. A dispensing device as claimed in claim 2 in which said obturatingmeans are associated with said stem to open said flow paths when saidstem is moved into said valve body, and said actuator means is connectedwith said valve stem for moving said valve stem into said valve body.

6. A dispensing device as claimed in claim 5 in which said actuatormeans comprises an actuator sleeve on said valve stem, at least twolevers pivotally mounted on said valve assembly and having one endengaged with said sleeve, an an actuator pivotally connected to theother end of each of said levers and to said piston rod.

7. A dispensing device as claimed in claim 2 in which said device hasfinger grips thereon for enabling the device to be gripped.

8. A dispensing device as claimed in claim 7 in which said device has ahousing around said valve assembly, cylinder and said sac holding themin association said finger grips being on said housing.

l I II 1 l

1. A dispensing device comprising: a valve assembly having a valve body,a valve stem movable through said valve body, said valve assembly havinga product flow path therethrough and a compressed air flow paththerethrough, part of one of said flow paths being through said stem,obturating means associated with said stem for obturating said flowpaths and actuated by said stem on movement of said stem to open theflow paths, and aspirating means at the upper end of said stem forbringing one end of each of said flow paths together, the other ends ofthe flow paths opening out of the valve body remote from said aspiratingmeans, a piston-cylinder assembly having a cylinder with one end aroundthe end of the compressed air flow path, a piston slidable in saidcylinder, a piston rod on said piston and extending out of the other endof said cylinder; product containing means coupled to the end of theproduct flow path remote from the aspirating means; and said piston andpiston rod and said valve assembly being operatively associated formoving said valve stem relative to said valve body for causing saidobturating means to open said flow paths when said piston is moved tothe inner end of said cylinder adjacent said valve assembly.
 2. Adispensing device comprising: a valve assembly having a valve body, ahollow valve stem movable through said valve body, said valve assemblyhaving a product flow path therethrough and a compressed air flow paththerethrough, part of one of said flow paths being through said stem,obturating means associated with said stem for obturating said flowpaths and actuated by said stem on movement of said stem to open theflow paths, and aspirating means at the upper end of said stem forbringing one end of each of said flow paths together, the other ends ofthe flow paths opening out of the bottom of the valve body; apiston-cylinder assembly having a cylinder with one end around the endof the compressed air flow path, a piston slidable in said cylinder, apistOn rod on said piston and extending out of the other end of saidcylinder; a product containing sac having a neck thereon sealed aroundthe end of the product flow path; and an actuator means connectedbetween said piston rod and said valve assembly for moving said valvestem relative to said valve body for causing said obturating means toopen said flow paths when said piston is moved to the inner end of saidcylinder adjacent said valve assembly.
 3. A dispensing device as claimedin claim 2 in which said piston rod and said piston have a boretherethrough.
 4. A dispensing device as claimed in claim 2 in which saidcylinder is engaged with the axial portion of said valve assembly, ahousing around said valve assembly and said cylinder and defining anannular space around said cylinder, said product sac being an annularsac and being positioned in said space, said housing having at least oneaperture therein for admitting air to said space.
 5. A dispensing deviceas claimed in claim 2 in which said obturating means are associated withsaid stem to open said flow paths when said stem is moved into saidvalve body, and said actuator means is connected with said valve stemfor moving said valve stem into said valve body.
 6. A dispensing deviceas claimed in claim 5 in which said actuator means comprises an actuatorsleeve on said valve stem, at least two levers pivotally mounted on saidvalve assembly and having one end engaged with said sleeve, an anactuator pivotally connected to the other end of each of said levers andto said piston rod.
 7. A dispensing device as claimed in claim 2 inwhich said device has finger grips thereon for enabling the device to begripped.
 8. A dispensing device as claimed in claim 7 in which saiddevice has a housing around said valve assembly, cylinder and said sacholding them in association said finger grips being on said housing.